Method of preparing dimensionally stable, flexible urethane foam and the foam produced thereby

Abstract

An open celled, dimensionally stable, flexible urethane foam and method of preparing such foam, which method comprises adding a cell opening dimensionally stabilizing amount of an additive to a foamable urethane composition, and thereafter foaming the composition containing such additive to provide a dimensionally stable, flexible urethane foam product. The additive mixture employed comprises an ester reaction product of a long chain acid with polyethylene or polypropylene glycols and/or contains free acid to provide for a desired acid value. The dimensionally stable, flexible foam product produced is particularly useful in the automotive industry as a flexible molded-type foam for use as cushions and seats.

What is claimed is: 
     
       1. A method of preparing a molded, high resilience, urethane foam product of improved dimensional stability, which method comprises: (a) adding to a foamable urethane composition a cell opening amount of a cell opening additive, which additive is selected from the group consisting of: (i) a long chain fatty acid;   (ii) a polyethylene or polypropylene glycol-long chain fatty acid ester; and   (iii) a mixture of "(i)" and "(ii)";     (b) reacting the foamable urethane composition in a closed mold to provide a high resiliency, molded urethane foam product; and   (c) recovering a molded foam product of improved dimensional stability and having a greater amount of open cells than the molded foam product produced without the cell opening additive.   
     
     
       2. The method of claim 1 which includes preparing a high resilient, molded urethane product by: (a) pouring the foamable urethane composition into an open mold;   (b) closing the mold and reacting the foamable urethane composition in the closed mold;   (c) opening the mold after preparation of the foam product; and   (d) removing the foam product from the mold.   
     
     
       3. The method of claim 1 wherein the said ester is present in an amount of from about 0.1 to 5 parts per 100 parts of polyol in the urethane composition. 
     
     
       4. The method of claim 1 wherein the fatty acid is present in an amount of from about 0.15 to 0.23 parts per 100 parts of polyol in the urethane composition. 
     
     
       5. The method of claim 1 wherein the fatty acid is a C 14  -C 22  fatty acid. 
     
     
       6. The method of claim 1 wherein the fatty acid is selected from the group consisting of: (a) oleic acid;   (b) stearic acid;   (c) stearolic acid;   (d) linolenic acid;   (e) linoleic acid;   (f) palmitic acid;   (g) palmitoleic acid;   (h) myristic acid;   (i) myristoleic acid; and   (j) mixtures thereof.   
     
     
       7. The method of claim 1 wherein the ester comprises a reaction product of a polyethylene glycol and a C 14  -C 22  fatty acid. 
     
     
       8. The method of claim 7 wherein the reaction product has an acid value of about 4.4 to 45. 
     
     
       9. The method of claim 1 wherein the ester comprises a polyethylene glycol-mono- or di-C 18  fatty acid, and mixtures thereof. 
     
     
       10. The method of claim 1 wherein the additive comprises a polyethylene glycol dioleate or linoleate. 
     
     
       11. The method of claim 1 wherein the mixture comprises a C 18  fatty acid and a polyethylene glycol C 18  fatty acid ester. 
     
     
       12. The method of claim 1 wherein the fatty acid comprises linoleic acid or oleic acid in an amount of 0.15 to 0.23 parts per 100 parts of the polyol of the urethane composition. 
     
     
       13. The method of claim 1 which includes mechanically treating the close molded foam product to increase the number of open cells. 
     
     
       14. The method of claim 13 which includes crushing the close molded foam product to increase the number of open cells. 
     
     
       15. The close molded foam product produced by the method of claim 1. 
     
     
       16. A method of preparing a molded, high resiliency, urethane foam product of improved dimensional stability, which method comprises: (a) adding to a foamable urethane composition a cell opening amount of a cell opening additive, which additive is selected from the group consisting of: (i) a C 18  fatty acid;   (ii) a polyethylene glycol-C 18  fatty acid ester; and   (iii) a mixture of "(i)" and "(ii)";     (b) introducing the composition containing the additive into an open mold;   (c) closing the mold to permit the preparation of the foam product;   (d) opening the mold; and   (e) recovering a high resiliency molded foam product of improved dimensional stability and having a greater amount of open cells than the molded foam product produced without the cell opening additive.   
     
     
       17. The method of claim 16 wherein the C 18  fatty acid is present in an amount of 0.15 to 0.23 per 100 parts of the polyol of the urethane composition. 
     
     
       18. The molded foam product produced by the method of claim 16. 
     
     
       19. The method of claim 1 wherein the foamable urethane composition contains a silicone cell promoter additive. 
     
     
       20. The molded foam provided by the method of claim 13.